In buildings equipped with hot water heating, the thermostatic radiator valves have been set by professionals to automatically regulate the indoor temperature. The surface temperature of the radiator will vary between lukewarm and hot, depending on the signal it receives from the thermostat. Simply put; the radiators will only be hot if the thermostat tells them to heat the room. Radiators are usually warmer at the top than the bottom.

So, the temperature in a room can be adjusted by using the radiator thermostat, by opening it or closing it slightly within the pre-set limits. If the temperature falls below +19 °C or rises above +23 °C and room-specific adjustments do not rectify the situation, a defect notification must be submitted. Residents cannot adjust the radiator adjustment valve settings or bleed the radiators themselves.

Do not cover thermostatic valves with large pieces of furniture or curtains. If you do so, the thermostat will stop the heating and the room will cool down. If the thermostat is located close to a ventilation window, which is then kept open, the thermostat will increase the heating to compensate. This will result in the radiator heating up too much and making the room too hot. Moreover, energy will also be wasted.

Research shows that a suitable indoor temperature is around +20–21 °C. A slightly lower temperature, of around +19 °C, is optimal for sleep.

Lowering the indoor temperature by one degree can reduce the energy required for heating by as much as 5–7 per cent.